Enhanced efficacy of immune checkpoint inhibitors with OK‑432 in malignant pleural mesothelioma: A case report

Yamada,Kazuki; Uemura,Takehiro; Mukai,Aya; Tanaka,Tatsuya; Sakakibara,Ippei; Ito,Keima; Mori,Yuta; Fukumitsu,Kensuke; Fukuda,Satoshi; Kanemitsu,Yoshihiro; Tajiri,Tomoko; Ito,Yutaka; Oguri,Tetsuya; Niimi,Akio

doi:10.3892/mco.2025.2872

September-2025 Volume 23 Issue 3

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September-2025 Volume 23 Issue 3

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Case Report

Enhanced efficacy of immune checkpoint inhibitors with OK‑432 in malignant pleural mesothelioma: A case report

Authors:
- Kazuki Yamada
- Takehiro Uemura
- Aya Mukai
- Tatsuya Tanaka
- Ippei Sakakibara
- Keima Ito
- Yuta Mori
- Kensuke Fukumitsu
- Satoshi Fukuda
- Yoshihiro Kanemitsu
- Tomoko Tajiri
- Yutaka Ito
- Tetsuya Oguri
- Akio Niimi
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Affiliations: Department of Respiratory Medicine, Allergy and Clinical Immunology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi 467‑8601, Japan
Article Number: 77
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Published online on: July 3, 2025

https://doi.org/10.3892/mco.2025.2872
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Abstract

Malignant pleural mesothelioma (MPM) is a rare and highly aggressive cancer with limited treatment options and poor prognosis. Although immunotherapy with ipilimumab (IPI) and nivolumab (NIVO) has the potential to improve outcomes, disease progression, including recurrent pleural effusions, often occurs during or after the initial treatment. OK‑432, an immunotherapeutic agent, is commonly used for pleurodesis to control malignant pleural effusions; however, its role in combination with immune checkpoint inhibitors (ICIs) remains underexplored. The present report describes 2 MPM cases in which patients initially responded to IPI and NIVO, but experienced disease progression. Following intrathoracic administration of OK‑432, the patients were successfully rechallenged with ICI therapy. Both cases exhibited sustained disease control and resolution of pleural effusions. These findings suggested that OK‑432 may modulate immune responses and potentially enhance the efficacy of ICIs. Further studies are warranted to validate the synergistic potential of OK‑432 and ICIs in MPM and other thoracic malignancies.

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Journals

International Journal of Molecular Medicine

International Journal of Oncology

Molecular Medicine Reports

Oncology Reports

Experimental and Therapeutic Medicine

Oncology Letters

Biomedical Reports

Molecular and Clinical Oncology

World Academy of Sciences Journal

International Journal of Functional Nutrition

International Journal of Epigenetics

Medicine International

Enhanced efficacy of immune checkpoint inhibitors with OK‑432 in malignant pleural mesothelioma: A case report

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